Square



Patented Jan. 14, 1941 UNITED STATES PATENT OFFICE 7 Claims.

This invention relates to a square for general use by mechanics and the like.

Various forms of squares and combination rules have heretofore been proposed wherein provision has been made for adjusting or separating the various elements of the devices. The present in- .vention proposes a try-square construction wherein a head portion and an angularly related blade portion may be readily assembled and disherein proposed resides in the fact that if, by

reason of Wear or otherwise, the proper angular relationship of the head and blade of the tool is disturbed, or if the absolute straightness of either element is impaired by reason of becoming nicked, warped, or otherwise mutilated, the elements may be separated, reground, and reassembled without change or adjustment in the attaching and assembling elements of the tool and without the necessity for any special rechecking of their final assembled accuracy. Further, the novel tool of my invention may, by disassembly, be reduced to small compass for packing or transportation.

An exemplary specific embodiment of a trysquare embodying the principles of my invention is set forth in detail in the following description and is illustrated in the accompanying drawing, wherein:

Fig. 1 is an elevational view of the assembled try-square with a portion of the head thereof broken away for clearness and with a preferred form of assembling and disassembling wrench in operating position with respect to the try-square;

Fig. 2 is a cross sectional view through the head portion of the try-square taken on the line 2-2 of Fig. l; and,

Fig. 3 is a perspective view of the locking rod and securing nut of the form of invention illustrated in the preceding figures.

In the drawing, like characters of reference denote like parts throughout the several figures,

and the numeral I0 designates a head or stock element for the try-square, such element being preferably substantially rectangular in cross sec- ,tion. A slot is formed in one end of the head element Ill to receive a relatively flat blade element II which, in the illustrated instance, is arranged to extend at right angles to the head element.

In the preferred form the upper and loweredges of the blade element H are formed to precise parallelism and the bottom of the slot in the head element I0 is formed in exact angular relation with respect to the right-hand or inner working edge of the head element 10, that angle in the present instance being- It will be seen from the foregoing that assurance of intimate and secure contact of the lower edge of the blade element H with the bottom of the slot in the head element I0 absolutely insures correct angular relationship of the working edges of the blade element l I with respect to the Working edge of the head element II].

In practice, the Width of the slot in the head element I0 is made just sufficiently large to conveniently accommodate the thickness of the blade element 1 l, but it will be seen hereafter that'the arrangement of the head and blade element securing parts and their cooperation is such that substantial clearance between the thickness of the blade and the width of the slot will not afiect rigidity and accuracy of the assembled tool.

One of the flat surfaces of the blade element I l is provided, adjacent its point of insertion in the slot in the head element Ill, with a surface recess [2 which is of inverted L-shape and thereby provides a locking portion l3, for receiving a locking rod. and a reduced entrance portion M.

The head element [0 is provided with an elongate opening which extends from its lower end, as seen in Figs. 1 and 2, nearly up to its upper end, but stopping short thereof to make for greater neatness and simplicity of appearance of the tool. This opening communicates with the slot in the upper end of the head element Id at one side, for which reason it is axially oil-set with respect to the slot. The axis of the elongate opening is disposed at a slight angle with respect to the direction of extent of the head element It) and this angularity is such that the opening, in its downward course, slants in a direction toward the vertical plane of the slot in the upper end of the element 10. A locking rod or pin I5 is disposed in the elongate opening of the head element l0 when the parts are in their assembled position. The lower end of the locking pin 15 is preferably threaded as at 16 and the lower end of the elongate opening in the head element H] is enlarged to receive a circular nut ll, such enlargement providing a ledge l8 against which the nut I1 is adapted to seat. The upper portion of the nut I1 as viewed in the drawing is internally threaded and the lower portion thereof is provided with a noncircular opening which may be hexagonal, as in the illustrated instance, for receiving the end of a manipulating wrench. One form of such wrench is shown in dot-and-dash lines at 19 in operating position in the opening in the nut l! in Fig. 1.

Adjacent its upper end the locking rod I5 is notched to provide an overhanging ledge 2U which, in assembled position, seats upon the lower edge of the portion l3 of the recess I2 in the face of the blade element ll. Above the overhanging ledge 26 the locking pin I5 is flattened as at 2| to accommodate the body portion of the blade element II and give broader bearing contact of the under surface of the ledge 20 on the lower side wall of the recess portion l3 than would otherwise be the case. The notch which forms the overhanging ledge 29 is undercut a degree sufficient to compensate for the agularity of disposition of the locking pin IS with respect to the plane of the blade element ll so that the overhanging ledge 20 may have flat and continuous contact with the upper surface of the lower edge of the portion 13 of the recess l2.

The head element It, the blade element II, and the locking pin it? are shown in Fig. 2 in their respective assembled positions. It will be seen, however, that if, through the medium of the Wrench l or the like, the nut ll be further rotated to engage a greater length of the threads H5 at the lower end of the locking pin l5, the engagement of the upper end of the nut IT against the ledge 58 will result in a tendency of the look-- ing pin to be forced downwardly in the direction of its prearranged angular disposition. Such movement will not only result in a greater downward force of the overhanging ledge 26 against the bottom surface of the recess portion l3, but, by virtue of the angular disposition of the locking pin l5, will have a definite horizontal force component (to the left as viewed in Fig. 2) which urges the blade element ll intimately into engagement with the left-hand wall of the slot in the upper end of the head element 50, as viewed in Fig. 2. Stated another way, there is in eifect, in the locking operation, a wedging of the upper end of the pin l5 between the blade H and the opposite wall of the pin receiving opening. See Fig. 2.

It is for this reason that formation of the slot in the head element l0 and the thickness of the blade element i l to precisely the same dimension is not critical in constructing a tool according to the principles of my invention, and in fact, even though for general reasons it is desirable to so construct the parts initially, the blade element it may subsequently have its surface reground within reasonable limits Without imp-airing the accuracy and continued utility of the tool upon subsequent reassembly.

While the tool so far illustrated and described is in the form of a try-square with the head and blade portions at an angle of 9G" with respect to each other, it will be apparent that other angular relationships are within the purview of my invention, and in fact, a number of differently related angular blades may comprise a set of blades for use with a single head element. Similarly, a number of blades varying in length may be provided for use with a given head element and blades projecting in opposite directions from the slotted head element may be employed to form T-squares. In the case of blades extending at angles other than 90, each blade will have a portion of its lower edge so arranged as to be; seated against the lower edge of the slot in the head element ID at right angles to the working edge of the latter, and another angularly related portion arranged to extend at the desired angle with respect to the working edge of the head element Ill.

When it is desired to disassemble the head and 2 blade elements I0 and I l, respectively, it is merely necessary to loosen the nut IT by use of the wrench IS. A very small degree of such loosening permits the blade element II to be moved to the right, as viewed in Fig. 1, until the entrance portion M of the recess I2 in the blade element is in alinement with the overhanging ledge 20 of the locking pin l5, whereupon the blade element may be removed by upward movement as viewed in Fig. 1. Subsequent reassembly is effected by a reversal of this process.

It is to be noted that the recess portion l3 extends substantially above and to the right of the upper end of the locking pin it as viewed in Fig. 1. For this reason both the side and end edges of the blade element l I may be reground without interfering with later reassembly of the device. If the left-hand end of the blade II as viewed in Fig. 1 be ground, the locking pin l5 will merely be disposed farther to the right in the recess por tion 13 when the parts are reassembled. To insure alinement of the left side of the head element 59 and the left end of the blade II, also as in Fig. 1, the tool may be placed with such side and end surfaces on a surface plate or the like while the locking pin is being tightened.

As is customary in tools of this class, the working surface of the head element Ill is relieved as at 24 to avoid any interference with the full availability of the angularly arranged working edges of the head element It and the blade element ll.

It will be apparent to those skilled in the art that certain changes may be made in the details of construction of the form of invention herein illustrated Without departing from the spirit or scope of my invention as defined in the appended claims.

- I claim:

1. In a square, a head portion having a slotted end, and a blade adapted to be rigidly disposed in said slotted end, a locking rod disposed in an opening in said head portion and extending therethrough obliquely, means at one end of said locking rod for engaging said blade and means at the other end of said locking rod for cooperation with the adjacent end of said head portion to urge said locking rod outwardly of said opening whereby to exert an oblique force against said blade to urge it simultaneously against the bottom and one side wall of said slot.

2. In a square, a head portion having a slotted end, and a blade adapted to be rigidly disposed in said slotted end, said blade having a recess in a face thereof adjacent said head portion, said recess comprising a portion extending lengthwise of said blade and spaced from a longitudinal edge thereof and a recess portion extending transversely from said edge to said first recess portion, a locking rod disposed in an opening in said head portion and having a projection at one end for engagement with said recess and means at its opposite end accessible from the opposite end of said head portion for moving said rod lengthwise to dispose said projection against a wall of the lengthwise portion of said recess and secure the blade against movement with respect to said head portion.

3. In a square, a head portion having a slotted end, and a blade adapted to be rigidly disposed in said slotted end, said blade having a recess in a face thereof adjacent said head portion, said recess comprising a portion extending lengthwise of said blade and spaced from an edge thereof and a recess portion extending from said edge to said first recess portion to provide an entrance to said lengthwise recess portion, a locking rod disposed in an opening in said head portion and extending therethrough obliquely, a projection at one end of said locking rod for engagement in said recess and means at the other end of said locking rod for cooperation with the adjacent end of said head portion to urge said locking rod outwardly of said opening whereby to exert an oblique force against said blade, said oblique force having a component downwardly into said slot and a component against the recess-bearing face of said blade to urge the latter firmly against a side wall of said slot.

4. In a square, a head portion having a slotted end, and a blade adapted to be rigidly disposed in said slotted end, a locking rod disposed in an opening in said head portion and extending therethrough, means at one end of said locking rod for engaging said blade and means at the other end of said locking rod for urging said locking rod outwardly of said opening whereby to urge said blade securely into said slotted end, said means comprising a nut disposed in an enlargement of said opening, said enlargement providing a ledge against which the end of said nut bears, said nut having an axial opening therethrough, the inner end of said opening being threaded to engage threads formed on the end of said locking rod and the outer end of said opening being noncircular to receive wrench means.

5. In a square, a head portion and a blade adapted to be rigidly disposed at an angle with respect thereto, a slot in an end of said head to receive said blade, said head having an opening extending from the end opposite said slot to a point of communication with said slot, said blade having a recess portion in one face thereof so disposed-as to be concealed by the slotted assembled and a transverse entry recess portion extending from the inner longitudinal edge of said blade to said first recess portion, a locking member disposed in said opening and having means adjacent said opposite end of the head for moving said member in a direction outwardly of said opposite end and for locking said member in such outwardly moved position, said locking member having a projection at its inner end for engagement in the recess in said blade to engage said blade and hold it forcibly in thebottom of said slot by moving said member outwardly to locking position.

6. In a square, a head portion having a slotted end, a blade adapted to be rigidly disposed in said slotted end, said blade having a recess in a face thereof adjacent said head portion, said recess comprising an oblong portion extending lengthwise of said blade and spaced from its longitudinal edges, and a recess portion extending transversely from one longitudinal edge of said blade to one end of said oblong recess portion to provide an entrance to the oblong recess portion, a locking rod disposed in an opening extending lengthwise of said head portion, a projection at one end of said locking rod for engagement in said oblong recess portion, and means at the other end of said locking rod for cooperation with the adjacent end of said head portion to urge said locking rod outwardly of said open- 7. In a square, a head portion having a slotted end, and a blade adapted to be rigidly disposed in said slotted end, said blade having an L-shaped recess in a face thereof adjacent said head portion, said L-shaped recess comprising a leg extending. lengthwise of said blade intermediate of the side edges thereof and a second leg extending transversely from a side edge of said blade to said first mentioned leg, a locking rod disposed in an opening extending lengthwise in said head portion and having a projection at one end for engagement in said recess and means at its opposite end accessible from the opposite end of said head portion for moving said projection against a lateral wall of the first mentioned leg of said recess, the second mentioned leg of said recess comprising an entrance portion for assembling said projection in said recess.

IGNATIUS B. BIALKOWSKI. 

